Start instant pot on saute mode. Add oil and cumin seeds.
Add onion paste and ginger and garlic. Stir and sauté for about 2 minutes till onion paste is light brown.
Tip in the spice powders one by one. First add turmeric powder, red chilli powder, salt and coriander powder and stir to combine well.
Add in the pureed tomatoes and cook the onion tomato masala for 3-4 minutes. Stir it continuously and cook till the masala starts releasing the oil.
Next, add in the soaked rajma in the instant pot stir to coat them with the masala.
Add 4 cups of water and close the instant pot lid.
Set the instant pot to pressure cook mode and set the timer to 20 minutes.
Once the pressure cooking cycle is complete allow to stand for 5 minutes and then release the pressure by moving the valve to the venting position.
Once pressure is fully released open the lid add chopped coriander or cilantro mix it and serve with steamed rice or roti.